1. Field of the Invention
This invention relates to firearms and, more particularly, to systems in which a propellant is ignited or initiated by energy.
2. Prior Art
In most firearms, the principal propellant charge is ignited by an ignition composition, such as a primer. The primer is usually mechanically initiated, such as by percussion by a firing pin or striker. This primer percussion technique has a number of undesirable features. In particular, firearms that use primer percussion require a complicated system of moving parts to produce the mechanical impulse necessary from a firing pin to cause ignition of the primer. This movement produces both a mechanical impact, which can generate movement of the weapon, and distinctive sounds. In addition, the primer and main propellant generate corrosive combustion products which can require frequent weapon maintenance. However, percussion primer systems are nonetheless widely used largely because they are relatively inexpensive and reliable.
To avoid drawbacks associated with percussion primer systems, others have proposed firearms and cartridges in which ignition of the propellant is electrically controlled (e.g., U.S. Pat. Nos. 3,362,329, 3,413,888, 3,563,177, 3,726,222 and 4,619,202) or laser initiated. U.S. Pat. Nos. 3,631,623 and 3,685,392 disclose firearms in which laser energy passes through a window at the bottom or side of a cartridge base and ignites a primary explosive. U.S. Pat. No. 3,408,937 discloses a pyrotechnic detonator, ignited by laser energy injected into it by a light-conducting pipe, in which the laser beam may be interdicted by a shutter.
It is an objective of the present invention to overcome problems in the prior art and provide a new and improved system for initiating a propellant.